Biomedical subjects

Eric J Seibel

Publications and source records attributed to Eric J Seibel.

6 recordsLinked to original sources

PubMed2006

Virtual reality helmet display quality influences the magnitude of virtual reality analgesia.

UNLABELLED: Immersive Virtual Reality (VR) distraction can be used in addition to traditional opioids to reduce procedural pain. The current study explored whether a High-Tech-VR helmet (ie, a 60-degree field-of-view head-mounted display) reduces pain more effectively than a Low-Tech-VR helmet (a 35-degree field-of-view head-mounted display). Using a double-blind between-groups design, 77 healthy volunteers (no patients) aged 18-23 were randomly assigned to 1 of 3 groups. Each subject received a brief baseline thermal pain stimulus, and the same stimulus again minutes later while in SnowWorld using a Low-Tech-VR helmet (Group 1), using a High-Tech-VR helmet (Group 2), or receiving no distraction (Group 3, control group). Each participant provided subjective 0-10 ratings of cognitive, sensory, and affective components of pain, and amount of fun during the pain stimulus. Compared to the Low-Tech-VR helmet group, subjects in the High-Tech-VR helmet group reported 34% more reduction in worst pain (P < .05), 46% more reduction in pain unpleasantness (P = .001), 29% more reduction in "time spent thinking about pain" (P < .05), and 32% more fun during the pain stimulus in VR (P < .05). Only 29% of participants in the Low-Tech helmet group, as opposed to 65% of participants in the High-Tech-VR helmet group, showed a clinically significant reduction in pain intensity during virtual reality. These results highlight the importance of using an appropriately designed VR helmet to achieve effective VR analgesia (see ). PERSPECTIVE: Pain during medical procedures (eg, burn wound care) is often excessive. Adjunctive virtual reality distraction can substantially reduce procedural pain. The results of the present study show that a higher quality VR helmet was more effective at reducing pain than a lower quality VR helmet.

Adolescent↗

PubMed2006

Using FMRI to study the neural correlates of virtual reality analgesia.

Excessive pain during medical procedures, such as burn wound dressing changes, is a widespread medical problem and is especially challenging for children. This article describes the rationale behind virtual reality (VR) pain distraction, a new non-pharmacologic adjunctive analgesia, and gives a brief summary of empirical studies exploring whether VR reduces clinical procedural pain. Results indicate that patients using VR during painful medical procedures report large reductions in subjective pain. A neuroimaging study measuring the neural correlates of VR analgesia is described in detail. This functional magnetic resonance imaging pain study in healthy volunteers shows that the large drops in subjective pain ratings during VR are accompanied by large drops in pain-related brain activity. Together the clinical and laboratory studies provide converging evidence that VR distraction is a promising new non-pharmacologic pain control technique.

Analgesia↗

PubMed2004

True three-dimensional displays that allow viewers to dynamically shift accommodation, bringing objects displayed at different viewing distances into and out of focus.

Under natural viewing conditions, viewers do not just passively perceive. Instead, they dynamically scan the visual scene by shifting their eye fixation and focus between objects at different viewing distances. In doing so, the oculomotor processes of accommodation (eye focus) and vergence (angle between lines of sight of two eyes) must be shifted synchronously to place new objects in sharp focus in the center of each retina. Accordingly, nature has reflexively linked accommodation and vergence, such that a change in one process automatically drives a matching change in the other. Conventional stereoscopic displays force viewers to try to decouple these processes, because while they must dynamically vary vergence angle to view objects at different stereoscopic distances, they must keep accommodation at a fixed distance--or else the entire display will slip out of focus. This decoupling generates eye fatigue and compromises image quality when viewing such displays. In an effort to solve this accommodation/vergence mismatch problem, we have built various prototype displays that can vary the focus of objects at different distances in a displayed scene to match vergence and stereoscopic retinal disparity demands and better simulate natural viewing conditions. By adjusting the focus of individual objects in a scene to match their stereoscopic retinal disparity, the cues to ocular accommodation and vergence are brought into agreement. As in natural vision, the viewer brings different objects into focus by shifting accommodation. As the mismatch between accommodation and vergence is decreased, natural viewing conditions are better simulated and eye fatigue should decrease.

Accommodation, Ocular↗

PubMed2004

Virtual vision loss simulator.

Vision loss is common among people over the age of 65 and the condition is irreversible in most cases. Our simulator is a means to effectively and accurately inform people about the nature of common vision problems, initially limited to medically accurate simulations of cataract and macular degeneration. Using an eye tracker that continuously determines the subject's fixation point, a systematically degraded digital image displayed on an HMD can be a powerful educational tool. This article presents our Virtual Vision Loss (VVL) simulator and the developed simulation techniques based on calibration from 27 subjects.

Adult↗

PubMed2003

A magnet-friendly virtual reality fiberoptic image delivery system.

A custom display was built into the MR radiofrequency headcoil to project high-resolution, wide field-of-view stereographic images. Advanced stimulus presentation technologies such as the one described could potentially contribute to a better understanding of the relation between what people are thinking or experiencing, and their associated patterns of brain activity (www.vrpain.com).

Computer Graphics↗

PubMed2002

Unique features of optical scanning, single fiber endoscopy.

BACKGROUND AND OBJECTIVE: To advance the field of minimally invasive medical procedures, an ideal endoscope should provide high-resolution images with variable magnification from an ultra-thin package, while adding depth cues and integrating optical diagnoses and therapies. Satisfying all these requirements is extremely difficult using commercial endoscopes. A new imaging technology is introduced that uses directed laser illumination, which is scanned at the distal end of a flexible endoscope. STUDY DESIGN/MATERIALS AND METHODS: A single-mode optical fiber is driven in vibratory resonance using a piezoelectric actuator. The emitted laser light is scanned in two-dimensions over test specimens. Digital images are constructed by detecting optical power one pixel at a time. RESULTS: Unique features of the fiber scanning scope are rapidly changing magnification, enhanced topographic detail, and concurrent fluorescence imaging, which are demonstrated and discussed. CONCLUSION: This fiber scanning scope has the potential for pixel-accurate delivery of high quality laser radiation, allowing the future integration of imaging with diagnosis and therapy.

Endoscopes↗